<template>
  <div class="count">
    <h2>当前的求和为{{ sum }}</h2>
    <select v-model="selValue">
      <option :value="1">1</option>
      <option :value="2">2</option>
      <option :value="3">3</option>
    </select>
    <button @click="add">加</button>
    <button @click="minus">减</button>
  </div>
</template>

<script setup lang="ts" name="Count">
  import { ref } from "vue";
  //数据
  let sum = ref(1); //当前的求和
  let selValue = ref(1); //用户选择的数字

  //方法
  function add() {
    sum.value += selValue.value;
  }

  function minus() {
    sum.value -= selValue.value;
  }
</script>

<style scoped>
  .count {
    background-color: skyblue;
    padding: 10px;
    border-radius: 10px;
    box-shadow: 0 0 10px;
  }

  select,
  button {
    margin: 0 5px;
    height: 25px;
  }
</style>
